Machine learning-based audio codec switching

ABSTRACT

Described herein are techniques, devices, and systems for providing an optimal voice experience over varying radio frequency (RF) conditions while using EVS audio codecs. A user equipment (UE) may adaptively transition between using a music-capable EVS codec (e.g., EVS-FB) as a default audio codec that provides a first audio bandwidth and a different EVS audio codec that provides a second audio bandwidth that is less than the first audio bandwidth. The transition to the different EVS audio codec may occur in response to determining a value indicative of a RF condition associated with a serving base station is less than a threshold value, which allows for providing preserving at least a minimal level of voice quality in degraded RF conditions.

BACKGROUND

The Enhanced Voice Services (EVS) codec is an audio codec that provideshigh quality sound for voice, as well as for generic audio such asmusic, and content that mixes voice and music. The Full Band of EVS(EVS-FB) provides extended audio bandwidth up to 20 kilohertz (kHz),which provides significant quality improvement for music and othersounds that are outside of the frequencies of sounds that the humanvoice can make. However, using EVS-FB as an audio codec for voice callsis not always better. For example, EVS-FB may be less efficient thanother audio codecs, and EVS-FB may consume more resources than necessarywhen voice is the only sound that matters. EVS-FB may also be unreliablein poor radio frequency (RF) conditions, such as when a user equipment(UE) moves farther from a cell site and close to the edge of the cell.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is set forth with reference to the accompanyingfigures, in which the left-most digit of a reference number identifiesthe figure in which the reference number first appears. The use of thesame reference numbers in different figures indicates similar oridentical items or features.

FIG. 1A is an example diagram illustrating a user on a voice call whilethe user is outside of a concert hall, in accordance with variousembodiments. A user equipment (UE) depicted in FIG. 1A establishes thevoice call using a first audio codec that provides a first audiobandwidth.

FIG. 1B is an example diagram illustrating the user depicted in FIG. 1Aon the same voice call while inside the concert hall, in accordance withvarious embodiments. The UE depicted in FIG. 1B transitions from usingthe first audio codec to using a second audio codec that provides asecond audio bandwidth greater than the first audio bandwidth. Thistransition occurs in response to detecting non-vocal frequencies (e.g.,music) in the environment.

FIG. 2 illustrates example components of the UE of FIGS. 1A and 1B, aswell as a technique for adaptively transitioning between audio codecsused by the UE during an ongoing communication session, in accordancewith various embodiments.

FIGS. 3A and 3B illustrate a flowchart of an example process foradaptively transitioning between audio codecs used by the UE during anongoing communication session, in accordance with various embodiments.FIG. 3A illustrates upgrading to a greater audio bandwidth, and FIG. 3Billustrates downgrading to a lesser audio bandwidth.

FIG. 4 illustrates a flowchart of an example process for outputting auser prompt prior to transitioning to using a different audio codec.

FIG. 5A illustrates an example user prompt that may be output on adisplay of a UE to request transitioning to a different audio codec.

FIG. 5B illustrates another example user prompt that may be output on adisplay of a UE to request transitioning to a different audio codec.

FIG. 5C illustrates another example user prompt that may be output on adisplay of a UE to request transitioning to a different audio codec.

FIG. 6 illustrates a flowchart of an example process for adaptivelytransitioning to a different audio codec based at least in part on a RFcondition.

FIG. 7 is an example diagram illustrating a technique for providing anoptimal voice experience over varying RF conditions while using EVSaudio codecs, in accordance with various embodiments.

FIGS. 8A and 8B illustrate a flowchart of an example process foradaptively transitioning between audio codecs used by the UE during anongoing communication session, in accordance with various embodiments.FIG. 8A illustrates downgrading to a lesser audio bandwidth, and FIG. 8Billustrates upgrading to a greater audio bandwidth.

FIG. 9 illustrates an example user prompt that may be output on adisplay of a UE to request transitioning to a different audio codec.

FIG. 10 illustrates a flowchart of an example process for adaptivelytransitioning to a different audio codec based at least in part ondetecting music in the environment of the UE.

FIG. 11 illustrates a flowchart of an example network-side process foradaptively transitioning a UE(s) between using different audio codecsduring an ongoing communication session, in accordance with variousembodiments.

FIG. 12 is a block diagram of an example communication device configuredto perform the techniques and processes described herein, in accordancewith various embodiments.

DETAILED DESCRIPTION

The Full Band of the Enhanced Voice Services codec (EVS-FB) provides asuperior sound experience than other EVS codecs. For example, a firstuser can play music while on a call with second user, and while EVS-FBis used as the audio codec for the call, the music sounds much betterand more realistic to the second user. However, this enhanced realismcomes at the cost of using more resources, both on the UE and on thenetwork. Accordingly, it may not be beneficial to always use EVS-FB asthe audio codec for calls involving UEs, even if both UEs are capable ofusing the EVS-FB codec. For example, the EVS-FB codec may be lessefficient than other audio codecs and/or unreliable in certainscenarios, as noted above.

Described herein are, among other things, techniques, devices, andsystems for selectively using a music-capable audio codec on-demandduring a communication session. Specifically, a UE may adaptivelytransition (or switch) between using a first audio codec (e.g., a firstEVS audio codec) that provides a first audio bandwidth and a secondaudio codec (e.g., a second EVS audio codec) that provides a secondaudio bandwidth that is greater than the first audio bandwidth. In someexamples, the first audio codec is a “less-than-full-band” EVS codec,such as the EVS Super Wideband (EVS-SWB) codec, the EVS Wideband(EVS-WB) codec, or even the EVS Narrowband (EVS-NB) codec. The secondaudio codec may be the EVS-FB codec. The transition to the second audiocodec may occur in response to a machine-learned determination thatsound in the environment of the UE includes frequencies outside of arange of frequencies associated with a human voice, such as by the UEusing a machine learning model(s) and/or artificial intelligence todetermine that music is being played in its environment. By adaptivelytransitioning between using these different audio codecs during anongoing communication session, a music-capable audio codec that providesgreater audio bandwidth (e.g., the EVS-FB codec) can be selectivelyutilized when it would be beneficial to do so, and other,less-than-full-band audio codecs can be utilized when it would not bebeneficial to utilize the music-capable audio codec.

In an illustrative example, a UE may include logic (e.g., software,firmware, hardware, or a combination thereof) for detecting sound in anenvironment of the UE and determining what frequencies are included inthe detected sound. This sound detection may be based on the output of atrained machine learning model(s) and/or an artificial intelligencealgorithm, and the sound detection may occur during an ongoingcommunication session, such as a Voice over New Radio (VoNR) session. Ifthe frequencies in the detected sound correspond to non-vocalfrequencies that are outside of a range of frequencies associated with ahuman voice (e.g., frequencies produced by music), the logic of the UEmay be configured to transition from using a first audio codec (e.g., aless-than-full-band EVS audio codec) to using a second audio codec thatprovides greater audio bandwidth (e.g., the EVS-FB codec). By continuingthe communication session using the second (music-capable) audio codec,non-vocal sounds, such as music, can be delivered with high-quality overan Internet Protocol (IP)-based network.

To further illustrate, if a first user calls a second user while thefirst user is located outside of a concert hall, the call may beestablished using the EVS-SWB codec, for example, because it may notmatter to the second user to hear non-vocal sounds in the environment ofthe first user (e.g., background noise), at least while the first useris located outside of the concert hall. Subsequently, the first user maywalk into the concert hall, at which point a first UE of the first userdetects music in the background, and the first UE, in response todetecting the background music, initiates a transition to using theEVS-FB codec, which provides an extended audio bandwidth that is betterfor music (or sound with a mixture of voice and music). In someimplementations, when the UEs switch to using the EVS-FB codec, thetransition can be automatic (i.e., without user intervention), or thetransition can be semi-automatic, such as by outputting, via the UE, auser prompt that requests to transition from using the first audio codecto using the second audio codec. After receiving user input authorizingthe UE to initiate the requested transition, the UEs may switch to usingthe second audio codec. For example, the first UE may send a message toa serving base station for transitioning to using the second audiocodec, and both of the UEs involved in the communication session maycontinue the communication session using the second audio codec,assuming both UEs support the EVS-FB audio codec.

The techniques, devices, and systems described herein for adaptivelytransitioning between using different audio codecs may allow one or moredevices to conserve resources with respect to processing resources,memory resources, networking resources, power resources, etc., in thevarious ways described herein. For example, by selectively using amusic-capable audio codec (e.g., the EVS-FB codec) on-demand, such as inresponse to detecting music in the environment of the UE, a UE(s) and/ora network node (e.g., a base station(s)) may conserve processingresources, battery power, and the like, and network efficiency may alsobe improved by allocating less network bandwidth to handle the sessiontraffic for a less-than-full-band EVS audio codec. In this manner, theuse of a music-capable audio codec (e.g., EVS-FB) can be reserved forinstances when it is most beneficial to use the music-capable audiocodec, which allows for providing an improved user experience wheneverthe music-capable audio codec is being used, and for conservingcomputing resources and/or improving network efficiency whenever themusic-capable audio codec is not being used. In some scenarios, UEs thatare involved in an ongoing communication may switch back-and-forthmultiple times between audio codecs in order to realize theaforementioned benefits.

Also described herein are techniques, devices, and systems for providingan optimal voice experience over varying radio frequency (RF) conditionswhile using EVS audio codecs. For example, logic of a UE may beconfigured to adaptively transition, during an ongoing communicationsession, from using a music-capable EVS codec (e.g., EVS-FB) as adefault (or preferred) audio codec to using a different EVS audio codecthat provides a decreased audio bandwidth (e.g., EVS-SWB with ChannelAware Mode (CAM)). The transition from using the music-capable codec tousing the different EVS audio codec may be triggered, at least in part,by a degradation of a RF condition(s) below a particular threshold. Byadaptively transitioning between using these different audio codecsduring an ongoing communication session, at least a minimal level ofvoice quality can be maintained for a communication session whiledegraded the RF condition(s) are present.

To illustrate, two UEs involved in a communication session (e.g., a VoNRcall) may each support using the EVS-FB codec. Accordingly, thecommunication session may be established using the EVS-FB codec as adefault (or preferred) audio codec, and the UEs may continue to use theEVS-FB codec while a RF condition(s) is/are good (e.g., equal to orgreater than a threshold(s) level). Examples of RF conditions that maybe monitored include, without limitation, a radio signal strengthindication (RSSI) parameter, a reference signal received power (RSRP)parameter, and/or a reference signal received quality (RSRQ) parameter,among other possible RF conditions. By using the EVS-FB codec duringgood (e.g., above-threshold) RF conditions, an optimal sound experiencecan be provided to the parties of the communication session. However, ifat some point during the communication session the RF condition(s)associated with the serving base station degrades past a certain point,the logic of the UE may transition from using the EVS-FB codec to aless-than-full-band EVS audio codec, such as the EVS-SWB codec with CAM.In some implementations, the EVS-SWB codec may be used at a bit rate ofabout 13.2 kilobits per second (kbps), which is a bit rate that providesa notable link budget gain to the UEs involved in the communicationsession, as compared to using a legacy audio codec, such as AdaptiveMulti-Rate Wideband (AMR-WB), and which is preferable to using theEVS-FB codec in degraded RF conditions. That is, it is better totransition from using the EVS-FB codec to using the EVS-SWB codec withCAM at a bit rate of about 13.2 kbps whenever RF conditions degrade pasta certain point, because doing so provides a link budget gain (e.g.,improved signal strength) to the UEs close to the cell edge, and becausecontinuing the session using the EVS-FB codec may not provide anequivalent link budget gain in poor RF conditions. After transitioningto using the EVS-SWB codec, for example, the supreme sound experiencethat is offered by the EVS-FB codec is traded for a better-soundingvoice call (e.g., better voice quality, so that one user can understandwhat the other user is saying). That is, in certain RF conditions, theEVS-FB codec is unable to provide a minimal level of voice quality inorder to carry on an intelligible conversation because EVS-FB audioframes may be dropped or corrupted, which degrades the audio quality.These degraded RF conditions may occur if the UE moves away from thecell site and close to the cell edge where coverage is marginal, and/orif there is interference at a certain location of the UE.

The techniques, devices, and systems described herein for adaptivelytransitioning to using a less-than-full-band EVS audio codec (e.g., theEVS-SWB codec with CAM at a bit rate of about 13.2 kbps) in degraded RFconditions allows for maintaining at least a minimal level of voicequality for a communication session. This is due, in part, to the factthat the EVS-SWB codec with CAM provides partial audio packet redundancythrough audio frame replication, which provides extra protection toaudio payloads, which, in turn, provides better audio quality for voicein poor RF conditions, as compared to using the EVS-FB codec in thesame, or similar, RF conditions.

Also disclosed herein are systems comprising one or more processors andone or more memories, as well as non-transitory computer-readable mediastoring computer-executable instructions that, when executed, by one ormore processors perform various acts and/or processes disclosed herein.

FIG. 1A is an example diagram illustrating a user 100 on a call 102(e.g., a VoNR session) while the user 100 is located outside of aconcert hall 104. The user 100 is holding a user equipment (UE) 106 andis using the UE 106 to establish the call 102 via a base station 108.The base station 108 may comprise any suitable type of cellular-based,and/or wireless-based, access point (e.g., a Next Generation Node B(gNB), an E-UTRAN Node B (eNodeB or eNB), etc.). In accordance withvarious embodiments described herein, the terms “cell site,” “celltower,” “base station,” “gNB,” “eNodeB,” and “eNB,” and may be usedinterchangeably herein to describe any base station 108 capable ofacting as a serving base station. The base station 108 may be capable ofcommunicating wirelessly using any suitable wireless communications/datatechnology, protocol, or standard, such as Global System for MobileCommunications (GSM), Time Division Multiple Access (TDMA), UniversalMobile Telecommunications System (UNITS), Evolution-Data Optimized(EVDO), Long Term Evolution (LTE), Advanced LTE (LTE+), Generic AccessNetwork (GAN), Unlicensed Mobile Access (UMA), Code Division MultipleAccess (CDMA), Orthogonal Frequency Division Multiple Access (OFDM),General Packet Radio Service (GPRS), Enhanced Data GSM Environment(EDGE), Advanced Mobile Phone System (AMPS), High Speed Packet Access(HSPA), evolved HSPA (HSPA+), Voice over IP (VoIP), Voice over LTE(VoLTE), voice over New Radio (VoNR)—e.g., 5G, IEEE 802.1x protocols,WiMAX, Wi-Fi, Data Over Cable Service Interface Specification (DOCSIS),digital subscriber line (DSL), and/or any future IP-based networktechnology or evolution of an existing IP-based network technology.

The UE 106 depicted in FIGS. 1A and 1B may be implemented as anysuitable computing device configured to communicate over a wirelessnetwork, including, without limitation, a mobile phone (e.g., a smartphone), a tablet computer, a laptop computer, a portable digitalassistant (PDA), a wearable computer (e.g., electronic/smart glasses, ahead-mounted display (HMD), a smart watch, fitness trackers, etc.),and/or any similar UE. In accordance with various embodiments describedherein, the terms “wireless communication device,” “wireless device,”“communication device,” “mobile device,” “computing device,” “electronicdevice,” “user device,” and “user equipment (UE)” may be usedinterchangeably herein to describe any UE 106 capable of performing thetechniques and processes described herein. Furthermore, the UE 106depicted in FIGS. 1A and 1B may be capable of communicating wirelesslyusing any suitable wireless communications/data technology, protocol, orstandard, such as GSM, TDMA, UMTS, EVDO, LTE, LTE+, GAN, UMA, CDMA,OFDM, GPRS, EDGE, AMPS, HSPA, HSPA+, VoIP, VoLTE, VoNR—e.g., 5G, IEEE802.1x protocols, WiMAX, Wi-Fi, DOCSIS, DSL, and/or any future IP-basednetwork technology or evolution of an existing IP-based networktechnology.

Referring to FIG. 1A, the base station 108 may act as a “serving basestation” (or “serving cell”) for the UE 106, meaning that the basestation 108 depicted in FIG. 1A may be currently providing the UE 106with access to a telecommunication network, and/or that the base station108 may be actively setting up a communication session for the UE 106 toprovision such network access. In the illustrative example of FIG. 1A,the UE 106 has established a call 102 (e.g., a VoNR call), and the user100 may be talking to another user on the other end of the call 102. Forexample, the user 100 might call his wife to say (as shown in speechbubble 110): “Hey, our daughter is about to start her recital! Stay onthe line so you can listen!.” In this example, the user 100 intends tobring the UE 106 inside the concert hall 104 so that his wife can listento their daughter play music over the phone, during the ongoing call102.

FIG. 1A also illustrates that the UE 106 includes a vocoder(s) 112,which may represent logic (e.g., software, firmware, hardware, or acombination thereof) for encoding audio data generated using amicrophone of the UE 106 before it is transmitted to the serving basestation 108, and for decoding audio data that the UE 106 receives fromthe base station 108. The vocoder(s) 112 depicted in FIG. 1A hasestablished the call 102 using a first audio codec, which, in theexample of FIG. 1A, is the Enhanced Voice Services Super Wideband(EVS-SWB) codec. EVS is an audio codec standardized in the 3^(rd)Generation Partnership Project (3GPP) standard. EVS provides bettercapacity than its predecessor audio codecs, such as AMR, as well asbetter quality, and improved error resilience. Under the EVS “umbrella,”there are four specific types of EVS audio codecs, which are shown inTable 1, below, along with their respective audio bandwidths, samplingrates, and bit rates:

TABLE 1 Audio bandwidth EVS Codec (sampling rate) Bit rate Full Band(FB) 20 Hz to 20 kHz (48 kHz) 16.4 to 128 kbps Super Wideband 50 Hz to14 kHz (32 kHz) 9.6 to 128 kbps (SWB) Wideband (WB)  50 Hz to 7 kHz (16kHz) 5.9 to 128 kbps Narrowband (NB) 200 Hz to 3.4 kHz (8 kHz)   5.9 to24.4 kbps

A UE, such as the UE 106, may use Session Initiation Protocol (SIP) toestablish a communication session, such as the call 102, via the servingbase station 108. SIP is a signaling protocol that can be used toestablish, modify, and terminate communication sessions over packetnetworks, and to authenticate access to IP Multimedia Subsystem(IMS)-based services. As used herein, a “SIP request” is a message thatis sent from a UE 106 to the IMS core of the telecommunications networkusing SIP protocol, and a “SIP response” is a message that is sent fromthe IMS core of the telecommunications network to a UE 106 using SIPprotocol.

To establish the call 102 depicted in FIG. 1A, the UE 106 (in an examplewhere the UE 106 is acting as an originating UE) may send a sessionrequest, such as a SIP message using the SIP INVITE method, via theserving base station 108. The session request is sent to requestestablishment of the call 102 with a terminating device, such as anotherUE. The UE 106 may also send a Session Description Protocol (SDP) offeras part of this session request to specify, among other things,particular codecs, including audio codecs, that are supported by the UE106. The audio codecs supported by the UE 106 may be listed in order ofpreference, the first codec in the list being a preferred audio codec(or a default audio codec) that is used by default if the terminatingdevice also supports the preferred audio codec, and if the RF conditionsare good enough to use the preferred audio codec. In the example of FIG.1A, the UE 106 may list the EVS-SWB codec 114 as the first audio codecin the list of supported audio codecs, which indicates that the EVS-SWBcodec 114 is a preferred audio codec over other supported audio codecs,such as other EVS audio codecs. Accordingly, the call 102 may beestablished using the EVS-SWB codec 114 as a first audio codec. Asindicated in Table 1, above, the EVS-SWB codec 114 provides a firstaudio bandwidth of 50 hertz (Hz) to 14 kilohertz (kHz). This issufficient audio bandwidth to deliver speech content over an IP-basednetwork. Accordingly, the EVS-SWB codec 114 can be utilized while theuser 100 is outside of the concert hall 104 and while there is no musicbeing played in the background (i.e., in an environment of the UE 106).

The UE 106 may be further configured to execute an algorithm toadaptively transition between audio codecs used by the UE 106 during anongoing communication session, such as the call 102. In someimplementations, the transitioning between audio codecs may be triggeredby detecting sound in the environment of the UE 106 and by determiningthe frequencies that are included in the detected sound. In the exampleof FIG. 1A, the UE 106 may establish the call 102 using the EVS-SWBcodec 114 as a default (or preferred) audio codec in order to conserveresources, unless and until the UE 106 determines that it would bebeneficial to switch to using a music-capable audio codec, such as theEVS-FB codec. One way of making this determination is for the UE 106 toinclude logic that determines, based on audio data generated from soundin the environment of the UE 106, whether the sound includes frequenciesthat are outside of a range of frequencies associated with a humanvoice. In some examples, this range of frequencies may be apredetermined range of about 300 Hz to 3.4 kHz. In some examples, thedetermination made by the UE 106 is to determine whether music isplaying in the environment of the UE 106. In the example of FIG. 1A, thelogic of the UE 106 does not detect such out-of-range frequencies (e.g.,music) in the environment of the UE 106, so the UE 106 continues to usethe first audio codec, which is the EVS-SWB codec 114 in the example ofFIG. 1A. One example reason for using the EVS-SWB codec 114 in thescenario of FIG. 1A is because a less-than-full-band EVS audio codec canbe used with CAM, which provides the best coverage and efficiency, whichhelps to provide better voice quality when herein non-vocal sounds doesnot matter to the user on the other end of the call 102.

Turning to FIG. 1B, the user 100 depicted in FIG. 1A is still on thesame call 102, but the user 100 has now entered the concert hall 104,and the user's 100 daughter is playing the violin on stage as part of amusic recital. During the ongoing call 102, the UE 106 continuouslygenerates audio data based on sound in the environment of the UE 106. Ifthe user 100 is talking, some of this sound may represent speech utteredby the user 100, and that speech will most likely be in a typical vocalrange of frequencies (e.g., within a range of about 300 Hz to 3.4 kHz).However, as depicted in FIG. 1B, at least some of the sound in theenvironment of the UE 106 may include music frequencies 116 that areoutside of the range of frequencies associated with a human voice (e.g.,the music frequencies 116 created by the violin may be outside of arange of about 300 Hz to 3.4 kHz). Accordingly, the vocoder(s) 112 ofthe UE 106 may determine, based at least in part on the audio datagenerated by the UE 106 while inside of the concert hall 104, that thesound in the environment of the UE 106 includes frequencies that areoutside of vocal-frequencies (e.g., music frequencies 116). In someexamples, the vocoder(s) 112 specifically determines that music is beingplayed in the environment of the UE 106 based on the generated audiodata.

Based at least in part on determining that the sound in the environmentincludes the frequencies 116 that are outside of the range offrequencies associated with the human voice (e.g., based on determiningthat music is being played in the environment), the UE 106 depicted inFIG. 1B may initiate a transition from using the first audio codec(e.g., the EVS-SWB codec 114) to using a second audio codec thatprovides a second audio bandwidth greater than the first audio bandwidthprovided by the first audio codec. For example, the second audio codecmay be the EVS-FB codec 118. As indicated in Table 1, above, the EVS-FBcodec 118 provides a second audio bandwidth of 20 Hz to 20 kHz, which isgreater than the first audio bandwidth of 50 Hz to 14 kHz provided bythe EVS-SWB codec 114. As used herein, a second audio bandwidth is“greater than” a first audio bandwidth if the frequency rangecorresponding to the second audio bandwidth is larger than the frequencyrange corresponding to the first audio bandwidth.

In order to initiate the audio codec transition shown in FIG. 1B, the UE106 may send a message to the serving base station 108 for transitioningfrom using the first audio codec (e.g., the EVS-SWB codec 114) to usinga second audio codec (e.g., the EVS-FB codec 118). In some examples, themessage sent to the serving base station 108 may include a payloadheader that specifies the target (second) audio codec (e.g., the EVS-FBcodec 118). In some examples, the message includes a SDP offer and themessage is sent using Real-time Transport Control Protocol (RTCP), suchas an application-defined RTCP packet(s) (a RTCP-APP packet(s)). If theterminating device (e.g., the UE being used by the wife of the user 100)does not support the target (second) audio codec (e.g., if the user's100 wife is using a legacy UE), the call 102 may continue using the“lowest common denominator” audio codec, which may be the EVS-SWB codec114, in the example of FIGS. 1A and 1B. However, assuming that theterminating device also supports the target (second) audio codec, the UE106 can continue the call 102 using the second audio codec (e.g., theEVS-FB codec 118). In this way, the user on the other end of the call102 (e.g., the user's 100 wife) can experience the music frequencies 116with higher-fidelity and/or higher-quality by using the EVS-FB codec118, and the user's 100 wife may feel as though she is physicallypresent inside the concert hall 104, listening to her daughter play theviolin.

If the user 100 were to subsequently walk out of the concert hall 104,the UE 106 may be configured to transition audio codecs in the oppositedirection. That is, the UE 106 may be configured to transition fromusing the second audio codec (e.g., the EVS-FB codec 118) to using thefirst audio codec (e.g., the EVS-SWB codec 114) upon detecting sound inthe environment that no longer includes the out-of-range frequencies(e.g., the music frequencies 116). Accordingly, once the user 100 movesoutside of the concert hall 104 while carrying the UE 106, and while theUE 106 is still on the call 102, the UE 106 may send a second message tothe serving base station 108 for transitioning from using the secondaudio codec (e.g., the EVS-FB codec 118) to using the first audio codec(e.g., the EVS-SWB codec 114) once again. In this manner, resources areconserved by using the music-capable audio codec (e.g., the EVS-FB codec118) selectively (e.g., on-demand, as-needed, etc.). It is to beappreciated that other triggers besides ceasing to detect backgroundmusic may initiate the transition in the opposite direction (e.g.,transitioning from using the EVS-FB codec 118 to using the EVS-SWB codec114). For example, if a RF condition(s) falls below a predefinedthreshold, the UE 106 may transition back to the lesser audio bandwidthaudio codec. For example, if a RSSI value, a RSRP value, and/or a RSRQvalue determined (e.g., measured) by the UE 106 falls below a thresholdvalue(s), the UE 106 may determine that it is no longer efficient tocontinue using the music-capable audio codec (e.g., the EVS-FB codec118), and that voice quality may be improved by transitioning back tousing the EVS-SWB codec 114.

FIG. 2 illustrates example components of the UE 106 of FIGS. 1A and 1B,as well as a technique for adaptively transitioning between audio codecsused by the UE 106 during an ongoing communication session, inaccordance with various embodiments. As shown in FIG. 2, the UE 106 mayinclude one or more microphones 200, an EVS encoder 202, and acommunications (comms.) interface(s) 204. The microphone(s) 200 may beconfigured to capture sound and to convert the sound into digital audiodata 206. The microphone(s) 200 may represent a microphone array, suchas a beamforming array. The conversion of the sound into digital audiodata 206 may include using analogue-to-digital (A/D) conversion. Theaudio data 206 may be generated as one or more audio samples.

The EVS encoder 202 may represent the encoding part of the vocoder(s)112 depicted in FIGS. 1A and 1B, which may also include an EVS decoder(not shown). In some examples, the EVS encoder 202 may include amulti-rate audio encoder optimized for operation with voice andmusic/mixed content signals. Furthermore, the EVS encoder 202 may beinteroperable with AMR codecs. The EVS encoder 202 is configured toreceive, as input, the audio data 206 generated based on sound in anenvironment of the UE 106. An audio analyzer 208 of the EVS encoder 202may analyze the audio data 206 to determine whether the sound in theenvironment of the UE 106 includes frequencies outside of a range offrequencies 210 associated with a human voice, which may be apredetermined range that is stored in local memory of the UE 106. Asmentioned above, the range of frequencies 210 may be about 300 Hz to 3.4kHz, which represents a center portion of the audio bandwidth providedby the EVS-FB codec 118. In some implementations, frequencies that arewithin the range of frequencies 210 (e.g., vocal frequencies) aresubtracted or removed from the audio data 206 before the audio data 206is processed by the audio analyzer 208. This removal of vocalfrequencies may allow for isolating the frequencies of interest, such asnon-vocal frequencies (e.g., music), and/or it may otherwise removeunwanted noise emanating from the speaker of the UE 106 itself (e.g.,the voice of the other user on the call 102 being output from thespeaker of the UE 106). In some implementations, the audio analyzer 208is configured to determine, based on an analysis of the audio data 206,whether music is being played in the environment of the UE 106. In someimplementations, the audio analyzer 208 may process each audio sample itreceives. In other implementations, the audio analyzer 208 may processsome, but not all, of the audio samples in the audio data 206 generatedby the UE 106. For instance, the audio analyzer 208 may analyze audiodata 206 in response to an instruction or an event, and/or at anysuitable frequency or schedule (e.g., every few seconds) in order toconserve resources.

The audio analyzer 208 may use any suitable algorithm or technology tomake a determination based on the audio data 206 generated by the UE106. In some implementations, the audio analyzer 208 uses machinelearning and/or artificial intelligence to make a determination. Machinelearning generally involves processing a set of examples (called“training data”) in order to train a machine learning model(s). Amachine learning model(s), once trained, is a learned mechanism that canreceive new data as input and estimate or predict a result as output.For example, a trained machine learning model can comprise a classifierthat is tasked with classifying unknown input (e.g., an unknown image)as one of multiple class labels (e.g., labeling the image as a cat or adog). In some cases, a trained machine learning model is configured toimplement a multi-label classification task (e.g., labeling images as“cat,” “dog,” “duck,” “penguin,” and so on). Additionally, oralternatively, a trained machine learning model can be trained to infera probability, or a set of probabilities, for a classification taskbased on unknown data received as input. In the context of the presentdisclosure, the unknown input may include the audio data 206 (e.g., oneor more audio data samples) that represents sound in the environment ofthe UE 106, and the trained machine learning model(s) may be tasked withoutputting a probability of the sound including frequencies outside of arange of frequencies 210 associated with a human voice. In someimplementations, the trained machine learning model(s) may output aprobability that music is being played in the environment. Because musicis just one example type of sound that may be of interest to a userinvolved in a communication session, the machine learning model(s) maybe trained to detect other types of non-vocal (or non-speech) sounds ofinterest. In the example where the sound of interest is music, themachine learning model(s) may be trained to distinguish background musicfrom other non-vocal (or non-speech) background noises (e.g., a catmeowing in the vicinity of the UE 106, a motorcycle driving by the UE106, etc.). In some implementations, the machine learning model(s) maybe trained to distinguish between background music at various decibellevels, which may allow for detecting music in an environment when musicis intended to be conveyed as a sound of interest, and not detectingmusic when music is not intended to be conveyed as a sound of interest,even when music is softly playing in the background (e.g., when the user100 is in an elevator with music. In some embodiments, the probabilityoutput from the trained machine learning model(s) is a variable that isnormalized in the range of [0,1]. In some implementations, the trainedmachine learning model(s) may output a set of probabilities (e.g., twoprobabilities), where one probability relates to the probability ofmusic being played in the background, and the other probability relatesto the probability of music not being played in the background. Theprobability that is output by the trained machine learning model(s) canrelate to either of these probabilities (detected music or no detectedmusic) to indicate a level of confidence that there is or is not musicin the background.

A trained machine learning model(s) used by the audio analyzer 208 mayrepresent a single model or an ensemble of base-level machine learningmodels, and may be implemented as any type of machine learning model.For example, suitable machine learning models for use by the audioanalyzer 208 include, without limitation, neural networks, tree-basedmodels, support vector machines (SVMs), kernel methods, random forests,splines (e.g., multivariate adaptive regression splines), hidden Markovmodel (HMMs), Kalman filters (or enhanced Kalman filters), Bayesiannetworks (or Bayesian belief networks), expectation maximization,genetic algorithms, linear regression algorithms, nonlinear regressionalgorithms, logistic regression-based classification models, or anensemble thereof. An “ensemble” can comprise a collection of machinelearning models whose outputs (predictions) are combined, such as byusing weighted averaging or voting. The individual machine learningmodels of an ensemble can differ in their expertise, and the ensemblecan operate as a committee of individual machine learning models that iscollectively “smarter” than any individual machine learning model of theensemble.

The training data that is used to train a machine learning model fordetecting background music may include various types of data. Ingeneral, training data for machine learning can include two components:features and labels. However, the training data used to train a machinelearning model(s) used by the audio analyzer 208 may be unlabeled, insome embodiments. Accordingly, the machine learning model(s) used by theaudio analyzer 208 may be trainable using any suitable learningtechnique, such as supervised learning, unsupervised learning,semi-supervised learning, reinforcement learning, and so on. Thefeatures included in the training data can be represented by a set offeatures, such as in the form of an n-dimensional feature vector ofquantifiable information about an attribute of the training data. Aspart of the training process, weights may be set for machine learning.These weights may apply to a set of features included in the trainingdata. In some embodiments, the weights that are set during the trainingprocess may apply to parameters that are internal to the machinelearning model(s) (e.g., weights for neurons in a hidden-layer of aneural network). These internal parameters of the machine learningmodel(s) may or may not map one-to-one with individual input features ofthe set of features. The weights can indicate the influence that anygiven feature or parameter has on the probability that is output by thetrained machine learning model.

In some implementations, the audio analyzer 208 may be configured tosend audio data 206 to a remote audio processing system over a computernetwork (e.g., over the telecommunication network via the serving basestation 108) in real-time, and the remote audio processing system, whichis remotely located from the UE 106, may process the audio data 206(e.g., using machine learning techniques, as described herein) to make adetermination as to whether music is being played in an environment ofthe UE 106, and the remote system may send information and/or aninstruction to the UE 106 that indicates whether music is being playedin the environment of the UE 106 and/or that instructs the UE 106 toadaptively transition to a different audio codec. An examplenetwork-side process 1100 that may be implemented by such a remote audioprocessing system is described with reference to FIG. 11, below.

In either scenario (i.e., local processing or remote processingscenarios), if the audio analyzer 208 determines to transition to adifferent audio codec, the output of the audio analyzer 208 may beprovided to a codec adapter 212 of the EVS encoder 202. In someimplementations, the output of the audio analyzer 208 instructs thecodec adapter 212 to transition to a particular audio codec, such as byspecifying the EVS-FB codec 118, or another codec that is the targetaudio codec. In other implementations, the output of the audio analyzer208 informs the codec adapter 212 as to which frequencies are includedin the sound in the environment of the UE 106 (e.g., if musicfrequencies 116 are detected), and the codec adapter 212 selects theappropriate audio codec for the detected frequencies output by the audioanalyzer 208. FIG. 2 illustrates available EVS audio codecs 214 that maybe selected by the codec adapter 212. For example, the codec adapter 212may select the EVS-FB codec, the EVS-SWB codec, the EVS-WB codec, or theEVS-NB codec as the target audio codec. In the illustrative example ofFIGS. 1A and 1B, the UE 106 may be involved in a communication session(e.g., a call 102) using the EVS-SWB codec 114, and the codec adapter212 may select the EVS-FB codec 118 from the list of available EVS audiocodecs 214 based on output received from the audio analyzer 208, whichmay indicate that music is playing in the background, or which mayotherwise instruct the codec adapter 212 to transition to using theEVS-FB codec 118.

To initiate the transition to the target audio codec, the output of thecodec adapter 212 may be received by the communications interface(s)204, which may include a payload formatter that is configured to send amessage to the serving base station 108 for transitioning from using thecurrent audio codec to using a target audio codec that provides adifferent audio bandwidth than the audio bandwidth provided by thecurrent audio codec.

Although machine learning and/or artificial intelligence is provided asan example technique that may be used by the audio analyzer 208 todetect music being played in an environment of the UE 106, it is to beappreciated that other non-machine learning techniques may be utilizedto determine that music is being played in the environment of the UE106. For example, the audio analyzer 208 may be configured to analyzethe frequencies in the audio data 206 and compare the identifiedfrequencies to the range of frequencies 210 to determine if anyfrequencies are outside of the range of frequencies 210. In someimplementations, the audio analyzer 208 may determine if a loudness(e.g., measured in decibels (dB)) of those out-of-range frequencies areabove a threshold loudness to avoid switching audio codecs in situationswhere the out-of-range frequencies are unlikely to be of interest to auser on the other end of the call 102 (e.g., noise from street traffic,wind, or even quiet music, such as elevator music, etc.). Furthermore,as will be described in more detail below, the audio analyzer 208 may beconfigured to cause the UE 106 to output a user prompt as a way ofallowing the user 100 to make the final determination as to whether theaudio codec is to be switched in the middle of a communication session.

The processes described in this disclosure may be implemented by thearchitectures described herein, or by other architectures. Theseprocesses are illustrated as a collection of blocks in a logical flowgraph. Some of the blocks represent operations that can be implementedin hardware, software, or a combination thereof. In the context ofsoftware, the blocks represent computer-executable instructions storedon one or more computer-readable storage media that, when executed byone or more processors, perform the recited operations. Generally,computer-executable instructions include routines, programs, objects,components, data structures, and the like that perform particularfunctions or implement particular abstract data types. The order inwhich the operations are described is not intended to be construed as alimitation, and any number of the described blocks can be combined inany order or in parallel to implement the processes. It is understoodthat the following processes may be implemented on other architecturesas well.

FIGS. 3A and 3B illustrate a flowchart of an example process 300 foradaptively transitioning between audio codecs used by the UE 106 duringan ongoing communication session, in accordance with variousembodiments. FIG. 3A illustrates upgrading to a greater audio bandwidth,and FIG. 3B illustrates downgrading to a lesser audio bandwidth. Fordiscussion purposes, reference is made to the previous figure(s) indescribing the process 300.

At 302, a UE 106 may establish, via a serving base station 108, acommunication session using a first audio codec that provides a firstaudio bandwidth. In some examples, the communication session is a voicecall 102, such as a VoNR session. If the UE 106 is acting as anoriginating UE, the UE 106 may send, at block 302, a session request,such as a SIP message using the SIP INVITE method, via the serving basestation 108 to request establishment of the call 102 with a terminatingdevice, such as another UE. The UE 106 may also send a SDP offer as partof this session request at block 302 to specify, among other things,particular codecs, including audio codecs, that are supported by the UE106. The audio codecs supported by the UE 106 may be listed in order ofpreference, the first codec in the list being a preferred audio codec(or a default audio codec that is used by default if the terminatingdevice also supports that audio codec, and if the RF conditions are goodenough to use that audio codec). Accordingly, the first audio codec maybe listed first in the list of supported audio codecs. In someimplementations, the first audio codec is a first EVS audio codec, suchas the EVS-WB codec 114 or the EVS-SWB codec.

At 304, the UE 106 may generate audio data 206 based on sound in anenvironment of the UE 106. This audio data 206 may be generated duringthe communication session (e.g., the voice call 102) established atblock 302 and/or the sound represented by the audio data 206 may havebeen captured using a microphone(s) 200 of the UE 106. If a user 100 ofthe UE 106 is talking when the audio data 206 is generated, the audiodata 206 may represent user speech. If music is playing in thebackground, the audio data 206 may represent music or a combination ofvoice and music.

At 306, the UE 106 (e.g., the audio analyzer 208) may determine based atleast in part on the audio data 206 (e.g., based on an analysis of theaudio data 206), whether the sound includes frequencies outside of arange of frequencies 210 associated with a human voice. In someimplementations, the determination at block 306 includes determiningwhether music is being played in the environment of the UE 106.Furthermore, as shown by blocks 308 and 310, the determination at block306 may utilize machine learning and/or artificial intelligencetechniques.

At 308, for instance, the audio data 206 may be provided as input to atrained machine learning model(s), as described herein. At 310, thetrained machine learning model(s) may generate, as output therefrom, aprobability that a source of at least some of the sound is not the humanvoice. For example, the probability may relate to a probability thatmusic is being played in the environment of the UE 106. In someimplementations, the UE 106 may determine whether the probabilitygenerated as output from the trained machine learning model(s) meets orexceeds a threshold probability to make the determination at block 306.If the UE 106 (e.g., the audio analyzer 208) determines that the sounddoes not include frequencies outside of a range of frequencies 210associated with a human voice, such as by determining that music is notbeing played in the environment of the UE 106, the process 300 mayfollow the NO route from block 306 to block 312 where the UE 106continues the communication session (e.g., the voice call 102) using thefirst audio codec, and the process 300 may proceed from block 312 toblock 304 to iterate the “upgrade” algorithm of FIG. 3A. If, at block306, the UE 106 (e.g., the audio analyzer 208) determines that the soundincludes frequencies outside of a range of frequencies 210 associatedwith a human voice, such as by determining that music is being played inthe environment of the UE 106, the process 300 may follow the YES routefrom block 306 to block 314.

At 314, the UE 106 may switch (e.g., initiate a transition) to using asecond audio codec that provides a second audio bandwidth greater thanthe first audio bandwidth provided by the first audio codec. As shown bysub-block 316, the switch at block 314 may involve sending a message tothe serving base station 108 for transitioning from using the firstaudio codec to using the second audio codec that provides the greater(e.g., extended) audio bandwidth. As described herein, the message sentat sub-block 316 may include a payload header that specifies the target,second audio codec, which may be a second EVS audio codec, such as theEVS-FB codec 118. In some examples, the message sent at sub-block 316includes a SDP offer and is sent using RTCP, such as a RTCP-APP packet.If the terminating device (e.g., the UE on the other end of thecommunication session) does not support the target, second audio codec,the session may continue using the “lowest common denominator” audiocodec, which may be the EVS-SWB codec 114 in the example of FIGS. 1A and1B. FIG. 3A depicts an example where both UEs support using the secondaudio codec (e.g., the EVS-FB codec 118).

At 318, the UE 106 may continue, via the serving base station 108, thecommunication session (e.g., the call 102) using the second audio codec,such as the EVS-FB codec 118. Accordingly, continuing the communicationsession at block 318 using the second audio codec may be based at leastin part on both UEs involved in the communication session supporting thesecond audio codec. In this way, the user on the other end of thecommunication session (e.g., the call 102) can experience non-vocalfrequencies, such as music frequencies 116, with higher-fidelity andhigher-quality using the EVS-FB codec 118.

As shown by the off-page reference “A” in FIGS. 3A and 3B, the process300 may continue from block 318 to block 320, which is shown in FIG. 3B.At 320, after having switched to using the second audio codec thatprovides greater audio bandwidth (e.g., the EVS-FB codec), the UE 106may generate additional/second audio data 206 based on sound in anenvironment of the UE 106. The operation(s) performed at block 320 maybe similar to the operation(s) performed at block 304, just at asubsequent time during the communication session (e.g., the call 102).

At 322, the UE 106 (e.g., the audio analyzer 208) may determine based atleast in part on the additional/second audio data 206 (e.g., based on ananalysis of the audio data 206), whether the sound includes frequenciesoutside of a range of frequencies 210 associated with a human voice. Theoperation(s) performed at block 322 may be similar to the operation(s)performed at block 306, including, for example, determining whethermusic is being played in the environment of the UE 106. Furthermore, asshown by blocks 324 and 326, the determination at block 322 may utilizemachine learning and/or artificial intelligence techniques. For example,the operation(s) performed at block 324 may be similar to theoperation(s) performed at block 308, and the operation(s) performed atblock 326 may be similar to the operation(s) performed at block 310,just on subsequently-generated audio data 206.

If the UE 106 (e.g., the audio analyzer 208) determines that the soundincludes (e.g., still includes) frequencies outside of a range offrequencies 210 associated with a human voice, such as by determiningthat music is being played in the environment of the UE 106, the process300 may follow the YES route from block 322 to block 328 where the UE106 continues the communication session (e.g., the voice call 102) usingthe second audio codec, and the process 300 may proceed from block 328to block 320 to iterate the “downgrade” algorithm of FIG. 3B. If the UE106 (e.g., the audio analyzer 208) determines that the sound no longerincludes frequencies outside of a range of frequencies 210 associatedwith a human voice, such as by determining that music is no longer beingplayed in the environment of the UE 106, the process 300 may follow theNO route from block 322 to block 330.

At 330, the UE 106 may switch (e.g., initiate a transition) to using thefirst audio codec that provides the first audio bandwidth less than thesecond audio bandwidth provided by the second audio codec. As shown bysub-block 332, the switch at block 330 may involve sending a secondmessage to the serving base station 108 for transitioning from using thesecond audio codec to using the first audio codec that provides thelesser audio bandwidth. The operation(s) performed at sub-block 332 maybe similar to the operation(s) performed at sub-block 316, except that adifferent target audio codec is specified to transition audio codecs inthe opposite direction relative to FIG. 3A.

At 334, the UE 106 may continue, via the serving base station 108, thecommunication session (e.g., the call 102) using the first audio codec,such as the EVS-SWB codec 114. Continuing the communication session atblock 334 using the first audio codec may be based at least in part onboth UEs involved in the communication session supporting the firstaudio codec. In this way, resources are conserved by refraining fromutilizing the music-capable, second audio codec at a time when doing sowould utilize more resources than necessary, and the less-then-full-bandfirst audio codec is sufficient for voice as the primary sound ofinterest.

As shown by the off-page reference “B” in FIGS. 3A and 3B, the process300 may continue from block 334 to block 304, which is shown in FIG. 3Ain order to iterate the algorithm for switching back and forth betweenaudio codecs during the ongoing communication session.

FIG. 4 illustrates a flowchart of an example process 400 for outputtinga user prompt prior to transitioning to using a different audio codec.For discussion purposes, reference is made to the previous figures indescribing the process 400.

At 402, a UE 106 may determine (e.g., based on sound detected in anenvironment of the UE 106) to request switching from using an existingaudio codec currently being used for an ongoing communication session(e.g., a call 102) to using a different audio codec. For example, the UE106 may detect out-of-range frequencies (e.g., music playing) in theenvironment of the UE 106, as described with respect to FIG. 3A, and theUE 106 may determine to request upgrading from a first audio codec to asecond audio codec that provides greater audio bandwidth. Alternatively,the UE 106, at block 402, may not detect out-of-range frequencies (e.g.,no music playing) in the environment of the UE 106, as described withrespect to FIG. 3B, and the UE 106 may determine to request downgradingfrom a second audio codec to a first audio codec that provides lesseraudio bandwidth.

At 404, in response to the determination at block 402, the UE 106 mayoutput a user prompt associated with transitioning (e.g., requesting totransition) to a different audio codec. If upgrading to a greater audiobandwidth, the user prompt may be output at block 404 in response todetermining that music is being played in the environment of the UE 106,for example. In this scenario, the user prompt may indicate that the UE106 detected background music and the user prompt may request totransition from an existing audio codec to a different audio codec thatprovides a greater audio bandwidth, such as the EVS-FB codec (or asimilar music-capable audio codec). If downgrading to a lesser audiobandwidth, the user prompt may be output at block 404 in response todetermining that music is no longer being played in the environment ofthe UE 106, for example. In this scenario, the user prompt may indicatethat the UE 106 has ceased detecting background music and the userprompt may request to transition from an existing audio codec to adifferent audio codec that provides a lesser audio bandwidth, such asthe EVS-SWB codec or the EVS-WB codec.

At 404, the user prompt may be output via a display of the UE 106, suchas a visual user prompt with text informing the user 100 as to what theuser prompt is about and with selection elements presented on thedisplay for selection by the user 100. Additionally, or alternatively,the user prompt may be an audible prompt that is output via a speaker(s)of the UE 106, and/or a vibratory prompt via a mechanical actuator, etc.

At sub-block 406, the user prompt may request a selection of a bit rateamong multiple available bit rates to use with the different audiocodec. For example, if upgrading to the EVS-FB codec, the user promptmay request a selection of a bit rate among multiple available bit rateswithin a range of 16.4 to 128 kbps. The user's selection of a particularbit rate may dictate the bit rate that is selected by the codec adapter212.

At 408, the UE 106 may determine whether to switch to the differentaudio codec. As part of this determination, the UE 106 may determinewhether user input is received at block 410. If, for example, no userinput is received via the UE 106, the user prompt may timeout and theprocess 400 may follow the NO route from block 408 to block 412, wherethe UE 106 may continue to use the existing audio codec instead ofswitching to using the different audio codec. In other words, in theabsence of explicit approval from the user 100 (indicated via userinput) to switch to the different audio codec, the UE 106 (e.g., thecodec adapter 212) may refrain from switching to a different audiocodec. In other implementations, the UE 106, at block 410, receive userinput to refrain from transitioning to using the different audio codec,and based on this user input, the process 400 may follow the NO routefrom block 412 to continue using the existing audio codec.

If, at 410, the UE 106 receives user input (e.g., via a touch screen ofthe UE 106, speech input, etc.) to transition to the different audiocodec, the process 400 may follow the YES route from block 408 to block414 where the UE 106 may transition to using the different audio codec.If upgrading, the user input received at block 410 may request totransition the from using a first audio codec (e.g., the EVS-SWB codec)to using a second audio codec (e.g., the EVS-FB codec). If downgrading,the user input received at block 410 may request to transition the fromusing the second audio codec (e.g., the EVS-FB codec) to using the firstaudio codec (e.g., the EVS-SWB codec). In some implementations, the UE106 may receive, at 410, a selection of a selected bit rate amongmultiple available bit rates that are made available for selection viathe user prompt, and the UE 106 may transition to using the differentaudio codec at the selected bit rate at block 414. Switching to using adifferent audio codec at block 414 may include sending a message to theserving base station 108 requesting to make the transition, such as themessage sent at sub-block 316 or sub-block 332 of the process 300.

It is to be appreciated that the transition to using a different audiocodec may occur without user intervention instead of implementing theprocess 400. However, the process 400 allows the user 100 of the UE 106to have a say in whether to switch to a different audio codec or not.For instance, if the UE 106 detects music in the background and the UE106 prompts the user 100 to switch to the EVS-FB codec 118, the user 100may nevertheless decide that the music would not be of interest to theother user on the call 102, and the user 100 may ignore the user promptin this situation, or the user 100 may provide user input to explicitlyrefrain from transitioning to the different audio codec. In the oppositedirection, the UE 106 may recommend switching to the EVS-SWB codec 114,but the user 100 may wish to continue using the EVS-FB codec 118 if theuser 100 would like the other user to hear background music inhigh-fidelity despite other advantages in using a less-than-full-bandEVS audio codec.

FIG. 5A illustrates an example user prompt 500 that may be output on adisplay 502 of a UE 106 to request transitioning to a different audiocodec. In the example of FIG. 5A, a user 100 of the UE 106 has calledanother user named Yasmin. The call 102 may have been established usinga first audio codec that provides a first audio bandwidth (e.g., theEVS-SWB codec 114), as described herein. During the call 102, the UE 106may generate audio data 206 based on sound in an environment of the UE106, and the UE 106 (e.g., the audio analyzer 208) may determine, basedat least in part on an analysis of the audio data 206, that music isbeing played in the environment of the UE 106. Accordingly, the UE 106may determine to request switching to a second audio codec (e.g., theEVS-FB codec 118) based on this sound detection.

In response to determining that the music is being played in theenvironment, the UE 106 may output (e.g., via the display 502) the userprompt 500. The user prompt 500 may indicate that the UE 106 detectedbackground music, and the user prompt 500 may ask permission or requestto transition from using the first audio codec to using a second audiocodec (e.g., the EVS-FB codec 118) that provides a second audiobandwidth greater than the first audio bandwidth. For example, the userprompt 500 may ask the user 100 if the user 100 would like to switch toa music call for better sound quality. Furthermore, the user prompt 500may output selection elements 504 (e.g., soft buttons) on the display502, such as a “YES” element 504(1) and a “NO” element 504(2). The user100 may provide user input by selecting one of the selection elements504. If the UE 106 receives user input (e.g., via the display 502, whichmay be a touchscreen) selecting the “YES” element 504(1) to transitionfrom using the first audio codec to using the second audio codec, the UE106 may send a message to the serving base station 108 for transitioningto the second audio codec, and the UE 106 may continue the call 102using the second audio codec. If the UE 106 receives user inputselecting the “NO” element 504(2) to refrain from transitioning, or ifno user input is received and the user prompt 500 times out (e.g., aftera number of seconds), the UE 106 may continue the call 102 using thefirst audio codec.

FIG. 5B illustrates another example user prompt 506 that may be outputon a display 502 of a UE 106 to request transitioning to a differentaudio codec. In the example of FIG. 5B, a user 100 of the UE 106 hascalled another user named Yasmin. The call 102 may have been establishedusing a first audio codec that provides a first audio bandwidth (e.g.,the EVS-SWB codec 114), as described herein. During the call 102, the UE106 may generate audio data 206 based on sound in an environment of theUE 106, and the UE 106 (e.g., the audio analyzer 208) may determine,based at least in part on an analysis of the audio data 206, that musicis being played in the environment of the UE 106. Accordingly, the UE106 may determine to request switching to a second audio codec (e.g.,the EVS-FB codec 118) based on this sound detection.

In response to determining that the music is being played in theenvironment, the UE 106 may output (e.g., via the display 502) the userprompt 506. The user prompt 506 may indicate that the UE 106 detectedbackground music, and the user prompt 500 may ask permission or requestto transition from using the first audio codec to using a second audiocodec (e.g., the EVS-FB codec 118) that provides a second audiobandwidth greater than the first audio bandwidth. For example, the userprompt 506 may ask the user 100 if the user 100 would like to switch toa music call at various bit rates for better sound quality. In theexample of FIG. 5B, the user prompt 506 may output selection elements508 (e.g., soft buttons) on the display 502. These selection elements508 may request selection of a bit rate among multiple available bitrates to use with the second audio codec. For example, a first selectionelement 508(1) is for switching to the second audio codec (e.g., theEVS-FB codec 118) at 16.4 kbps, a second selection element 508(2) is forswitching to the second audio codec at 24.4 kbps, a third selectionelement 508(3) is for switching to the second audio codec at 32 kbps,and a fourth selection element 508(4) is for switching to the secondaudio codec at 48 kbps. Of course more selection elements 508 may beoutput to offer additional bit rates (e.g., 64 kbps, 96 kbps, 128 kbps,etc.), other selection elements 508 may be output instead of those shownin FIG. 5B, or fewer selection elements 508 may be output, such as twoselection elements 508 for two different bit rates. A fifth selectionelement 508(5), upon selection, may cause the UE 106 to refrain fromswitching to the second audio codec.

The user 100 may provide user input by selecting one of the selectionelements 508. If the UE 106 receives user input (e.g., via the display502) selecting the selection element 508(2) as a selected bit rate (oras a selected element), the UE 106 may send a message to the servingbase station 108 for transitioning to the second audio codec at theselected bit rate of 24.4 kbps, and the UE 106 may continue the call 102using the second audio codec at the selected bit rate of 24.4 kbps. Ifthe UE 106 receives user input selecting the selection element 504(5) torefrain from transitioning, or if no user input is received and the userprompt 506 times out (e.g., after a number of seconds), the UE 106 maycontinue the call 102 using the first audio codec.

FIG. 5C illustrates another example user prompt 510 that may be outputon a display 502 of a UE 106 to request transitioning to a differentaudio codec. In the example of FIG. 5C, a user 100 of the UE 106 hascalled another user named Yasmin. The call 102 may have been establishedusing a first audio codec that provides a first audio bandwidth (e.g.,the EVS-SWB codec 114) and subsequently transitioned to using a secondaudio codec that provides a second, greater audio bandwidth (e.g., theEVS-FB codec 118), as described herein. During the call 102, and whilethe UE 106 is using the second audio codec, the UE 106 may generateaudio data 206 based on sound in an environment of the UE 106, and theUE 106 (e.g., the audio analyzer 208) may determine, based at least inpart on an analysis of the audio data 206, that music is no longer beingplayed in the environment of the UE 106. Accordingly, the UE 106 maydetermine to request switching back to the first audio codec (e.g., theEVS-SWB codec 114) based on this sound detection.

In response to determining that the music is no longer being played inthe environment, the UE 106 may output (e.g., via the display 502) theuser prompt 510. The user prompt 510 may indicate that the UE 106 hasceased detecting background music, and the user prompt 510 may askpermission or request to transition from using the second audio codec(e.g., the EVS-FB codec 118) to using the first audio codec (e.g., theEVS-SWB codec 114). For example, the user prompt 510 may ask the user100 if the user 100 would like to switch back to a traditional voicecall since the music has stopped. Furthermore, the user prompt 510 mayoutput selection elements 512 (e.g., soft buttons) on the display 502,such as a “YES” element 512(1) and a “NO” element 512(2). The user 100may provide user input by selecting one of the selection elements 512.If the UE 106 receives user input (e.g., via the display 502) selectingthe “YES” element 512(1) to transition from using the second audio codecto using the first audio codec, the UE 106 may send a message to theserving base station 108 for transitioning to the first audio codec, andthe UE 106 may continue the call 102 using the first audio codec. If theUE 106 receives user input selecting the “NO” element 512(2) to refrainfrom transitioning, or if no user input is received and the user prompt510 times out (e.g., after a number of seconds), the UE 106 may continuethe call 102 using the second audio codec.

FIG. 6 illustrates a flowchart of an example process 600 for adaptivelytransitioning between audio codecs based at least in part on a RFcondition. For discussion purposes, reference is made to the previousfigures in describing the process 600.

At 602, a UE 106 may determine, based on sound detected in anenvironment of the UE 106, to switch from using an existing audio codeccurrently being used for an ongoing communication session (e.g., a call102) to using a different audio codec. For example, the UE 106 maydetect out-of-range frequencies (e.g., music playing) in the environmentof the UE 106, as described with respect to FIG. 3A, and the UE 106 maydetermine to upgrade from a first audio codec to a second audio codecthat provides greater audio bandwidth.

At 604, in response to the determination at block 602, the UE 106 maydetermine (e.g., measure) a value(s) of a RF condition(s) associatedwith a serving base station 108. In some implementations, the value(s)may include, without limitation, a RSSI value, a RSRP value, and/or aRSRQ value.

At 606, the UE 106 may determine whether the value(s) indicative of theRF condition(s) is/are equal to or greater than a threshold value(s).For example, the UE 106 may determine whether a RSSI value is equal toor greater than a RSSI threshold value, and/or whether a RSRP value isequal to or greater than a RSRP value, and/or whether a RSRQ value isequal to or greater than a RSRQ value. If, at 606, the UE 106 determinesthat the value(s) is/are not equal to or greater than the thresholdvalue(s), the process 600 may follow the NO route from block 606 tocontinue using the existing audio codec at block 608. This is because,in poor (e.g., below-threshold) RF conditions, voice quality of a call102 may be improved by using a less-than-full-band EVS audio codec, asopposed to switching to using a music-capable audio codec, such as theEVS-FB codec 118. In other words, before switching to the EVS-FB codec118, for example, the UE 106 may check to make sure that the RFconditions are good enough to sustain a minimal quality voice call usingthe EVS-FB codec 118. If the RF conditions are not good enough, the UE106 may not switch to using the EVS-FB codec 118 notwithstanding adetection of music in the environment of the UE 106.

If, at 606, the UE 106 determines that the value(s) is/are equal to orgreater than the threshold value(s), the process 600 may follow the YESroute from block 606 to block 610 where the UE 106 may transition tousing the second audio codec (e.g., the EVS-FB codec). Switching tousing the second audio codec at block 610 may include sending a messageto the serving base station 108 requesting to make the transition, suchas the message sent at sub-block 316 of the process 300.

It is to be appreciated that additional or alternative factors besidesthe RF condition(s) may be taken into account in determining whether totransition to the second audio codec (e.g., the EVS-FB codec) or not.Such additional or alternative factors may include, without limitation,a location of the UE 106, a type communication session(s) that isongoing on the UE 106 (e.g., media playback, voice call 102, etc.),and/or whether carrier aggregation (e.g., New Radio Carrier Aggregation(NRCA) is being utilized for the communication session the UE 106 isinvolved in, among other possible factors.

FIG. 7 is an example diagram illustrating a technique for providing anoptimal voice experience over varying RF conditions while using EVSaudio codecs, in accordance with various embodiments. In order toprovide an optimal voice experience over varying RF conditions, the UE106 (e.g., the vocoder(s) 112) depicted in FIG. 7 may be configured toadaptively (e.g., during a communication session, such as a call 102)switch between using the EVS-FB codec 118 as a default audio codec and aless-than-full band EVS audio codec that provides decreased audiobandwidth, such as the EVS-SWB codec 114. For instance, at time, T1, theUE 106 may establish a communication session (e.g., a call 102) usingthe EVS-FB codec 118 by default for a better music experience in good(e.g., above-threshold) RF conditions. As shown in FIG. 7, the UE 106,at time, T1, may be relatively close to a center of a cell 700associated with the serving base station 108. When the UE 106 is at thelocation relative to the base station 108 shown at time, T1, in FIG. 7,values indicative of various RF conditions, such as a RSSI value, a RSRPvalue, and/or a RSRQ value, may be equal to or greater than a thresholdvalue(s), indicating that RF conditions are good enough, or that the RFconditions are sufficient for providing good voice quality (e.g., at orabove a minimal level of voice quality) to use the EVS-FB codec 118 asthe audio codec for the communication session (e.g., the call 102).

At time, T2, the UE 106 may move 702 to a new location close to the edgeof the cell 700. At some point during the movement 702 of the UE 106,the UE 106 may determine (e.g., detect, measure, etc.) a RF condition(s)(e.g., a RSSI value, a RSRP value, and/or a RSRQ value, etc.) anddetermine that the value(s) indicative of the RF condition(s) hasdecreased below a threshold value. Based at least in part on determiningthat the value(s) indicative of the RF condition(s) is less than thethreshold value(s), the UE 106 (e.g., the vocoder(s) 112) may transitionfrom using the EVS-FB codec 118 to using a less-than-full-band EVS audiocodec, such as the EVS-SWB codec 114 with CAM. Using the EVS-SWB codec114 with CAM may improve the voice quality of the call 102 in poor(e.g., below-threshold) RF conditions, such as when the user 100 carriesthe UE 106 to the edge of a cell's 700 coverage area. This improvementprovided by the less-than-full-band EVS audio codec is due, at least inpart, to the link budget gain provided by the less-than-full-band EVSaudio codec (e.g., EVS-SWB, EVS-WB, etc.), which may utilize CAM toprovide a link budget gain, meaning that the call 102 can be “carried” alittle bit farther from the base station by using the less-than-fullband EVS audio codec without a degradation in voice quality below aminimal level. If the call 102 were to continue using the EVS-FB codec118 at time, T2, packets may be dropped or corrupted because EVS-FB doesnot utilize an audio packet redundancy mechanism through audio framereplication. It is to be appreciated that, if and when the RFcondition(s) improves, the UE 106 (e.g., the vocoder(s) 112) can switchback to using the EVS-FB codec 118 for a better music experience inbetter RF conditions.

FIGS. 8A and 8B illustrate a flowchart of an example process 800 foradaptively transitioning between audio codecs used by the UE 106 duringan ongoing communication session, in accordance with variousembodiments. FIG. 8A illustrates downgrading to lesser audio bandwidth,and FIG. 8B illustrates upgrading to greater audio bandwidth. Fordiscussion purposes, reference is made to the previous figure(s) indescribing the process 800.

At 802, a UE 106 may establish, via a serving base station 108, acommunication session using the EVS-FB codec 118 as a default codec, theEVS-FB codec 118 providing a first audio bandwidth. In some examples,the communication session is a voice call 102, such as a VoNR session.If the UE 106 is acting as an originating UE, the UE 106 may send, atblock 802, a session request, such as a SIP message using the SIP INVITEmethod, via the serving base station 108 to request establishment of thecall 102 with a terminating device, such as another UE. The UE 106 mayalso send a SDP offer as part of this session request at block 802 tospecify, among other things, particular codecs, including audio codecs,that are supported by the UE 106. The audio codecs supported by the UE106 may be listed in order of preference, the first codec in the listbeing a preferred audio codec (or a default audio codec that is used bydefault if the terminating device also supports that audio codec, and ifthe RF conditions are good enough to use that audio codec). Accordingly,the EVS-FB codec 118 may be listed first in the list of supported audiocodecs at block 802. This is to provide a high-quality sound experience,such as to convey high-fidelity sound of non-vocal frequencies (e.g.,music) to the user on the other end of the call 102.

At 804, the UE 106 may determine, during the communication session, avalue(s) indicative of a RF condition associated with the serving basestation 108. The value(s) determined at block 804 may include, withoutlimitation, a RSSI value, a RSRP value, a RSRQ value, asignal-to-interference-plus-noise ratio (SINR) value, a bit rate value,a sample rate value, etc. The value(s) may be determined (e.g.,measured) by the UE 106 at block 804, and/or the value(s) may bereceived from the serving base station 108 at block 804, if, say, thevalue(s) was/were measured on the network side of the radio link.

At 806, the UE 106 may determine whether the value(s) determined atblock 804 is/are less than a threshold value(s). In someimplementations, the UE 106 may maintain threshold values in localmemory to compare the determined value(s) against.

If the UE 106 determines that the value(s) determined at block 804is/are not less than the threshold value(s) (indicating good RFconditions), the process 800 may follow the NO route from block 806 toblock 808 where the UE 106 continues the communication session (e.g.,the voice call 102) using the EVS-FB codec 118, and the process 800 mayproceed from block 808 to block 804 to iterate the “downgrade” algorithmof FIG. 3A. If, at block 806, the UE 106 determines that the value(s)determined at block 804 is/are less than the threshold value(s)(indicating poor RF conditions), the process 800 may follow the YESroute from block 806 to block 810.

At 810, the UE 106 may switch (e.g., initiate a transition) to using adifferent EVS audio codec that provides a second audio bandwidth lessthan the first audio bandwidth provided by the EVS-FB codec 118. Asshown by sub-block 812, the switch at block 810 may involve sending amessage to the serving base station 108 for transitioning from using theEVS-FB codec 118 to using the different EVS audio codec that providesthe lesser audio bandwidth. As described herein, the message sent atsub-block 812 may include a payload header that specifies the target,different audio codec, which may be a less-than-full-band EVS audiocodec, such as the EVS-SWB codec 114. In some examples, the message sentat sub-block 812 includes a SDP offer and is sent using RTCP, such as aRTCP-APP packet.

At 814, the UE 106 may continue, via the serving base station 108, thecommunication session (e.g., the call 102) using the different EVS audiocodec, such as the EVS-SWB codec 114. In some implementations, thedifferent EVS audio codec is the EVS-SWB codec 114 with CAM, and/or theEVS-SWB codec 114 used at a bit rate of about 13.2 kbps. Accordingly,continuing the communication session at block 814 using the different,less-than-full-band EVS audio codec may allow the call 102 to sustain atleast a minimal level of voice quality in degraded RF conditions. Thisis due, in part, to the fact that the EVS-SWB codec 114 with CAM, forexample, provides partial audio packet redundancy through audio framereplication, which provides extra protection to audio payloads, which,in turn, provides better audio quality for voice in poor RF conditions,as compared to using the EVS-FB codec 118 in the same, or similar, RFconditions.

As shown by the off-page reference “A” in FIGS. 8A and 8B, the process800 may continue from block 814 to block 816, which is shown in FIG. 8B.At 816, after having switched to using the different,less-than-full-band EVS audio codec that provides lesser audiobandwidth, the UE 106 may determine, during the communication session,another value(s) indicative of a RF condition associated with theserving base station 108. The operation(s) performed at block 816 may besimilar to the operation(s) performed at block 804, just at a subsequenttime during the communication session (e.g., the call 102).

At 818, the UE 106 may determine whether the value(s) determined atblock 816 is/are less than a threshold value(s). The operation(s)performed at block 818 may be similar to the operation(s) performed atblock 806. If the UE 106 determines that the value(s) determined atblock 816 is/are less than the threshold value(s) (indicating poor RFconditions), the process 800 may follow the YES route from block 818 toblock 820 where the UE 106 continues the communication session (e.g.,the voice call 102) using the different EVS audio codec, such as theEVS-SWB codec 114, and the process 800 may proceed from block 820 toblock 816 to iterate the “upgrade” algorithm of FIG. 8B. If, at block818, the UE 106 determines that the value(s) determined at block 816is/are not less than the threshold value(s) (indicating good/improved RFconditions), the process 800 may follow the NO route from block 818 toblock 822.

At 822, the UE 106 may switch (e.g., initiate a transition) to using theEVS-FB codec 118 that provides the first audio bandwidth greater thanthe second audio bandwidth provided by the different EVS audio codec. Asshown by sub-block 824, the switch at block 822 may involve sending asecond message to the serving base station 108 for transitioning fromusing the different EVS audio codec to using the EVS-FB codec 118 thatprovides the greater audio bandwidth. The operation(s) performed atsub-block 824 may be similar to the operation(s) performed at sub-block812, except that a different target audio codec is specified totransition audio codecs in the opposite direction relative to FIG. 8A.

At 826, the UE 106 may continue, via the serving base station 108, thecommunication session (e.g., the call 102) using the EVS-FB codec 118 toprovide an enhanced music experience in above-threshold RF conditions.Continuing the communication session at block 826 using the EVS-FB codec118 may be based at least in part on both UEs involved in thecommunication session supporting the EVS-FB 118 codec.

As shown by the off-page reference “B” in FIGS. 8A and 8B, the process800 may continue from block 826 to block 804, which is shown in FIG. 8Ain order to iterate the algorithm for switching back and forth betweenaudio codecs during the ongoing communication session.

FIG. 9 illustrates an example user prompt 900 that may be output on adisplay 502 of a UE 106 to request transitioning to a different audiocodec. In the example of FIG. 9, a user 100 of the UE 106 has calledanother user named Yasmin. The call 102 may have been established usingthe EVS-FB codec 118 to provide high-quality audio for music and mixedaudio content, as described herein. During the call 102, the UE 106 maydetermine that a value(s) indicative of a RF condition(s) associatedwith a serving base station 108 is less than a threshold value(s).Accordingly, the UE 106 may determine to request switching to adifferent EVS audio codec (e.g., the EVS-SWB codec 114) based on thisdegraded RF condition(s).

In response to determining that the value(s) indicative of the RFcondition(s) is less than the threshold value, the UE 106 may output(e.g., via the display 502) the user prompt 900. The user prompt 900 mayindicate that the UE 106 is currently using a full band of audiospectrum available and/or that it has detected poor coverage orreception, and the user prompt 900 may ask permission or request totransition from using the EVS-FB codec 118 to using a different EVSaudio codec (e.g., the EVS-SWB codec 114) that provides a decreasedaudio bandwidth, but that is likely to improve the voice quality of thecall 102. For example, the user prompt 900 may ask the user 100 if theuser 100 would like to switch to a traditional voice call to improve thevoice quality. Furthermore, the user prompt 900 may output selectionelements 902 (e.g., soft buttons) on the display 502, such as a “YES”element 902(1) and a “NO” element 902(2). The user 100 may provide userinput by selecting one of the selection elements 902. If the UE 106receives user input (e.g., via the display 502) selecting the “YES”element 902(1) to transition from using the EVS-FB codec 118 to usingthe different EVS audio codec, the UE 106 may send a message to theserving base station 108 for transitioning to the different EVS audiocodec, and the UE 106 may continue the call 102 using the different EVSaudio codec (e.g., the EVS-SWB codec 114 with CAM). If the UE 106receives user input selecting the “NO” element 902(2) to refrain fromtransitioning, or if no user input is received and the user prompt 900times out (e.g., after a number of seconds), the UE 106 may continue thecall 102 using the EVS-audio codec 118. It is to be appreciated that theprocess 400 may be utilized for outputting the user prompt 900 of FIG.9.

FIG. 10 illustrates a flowchart of an example process 1000 foradaptively transitioning between audio codecs based at least in part ondetecting music being played in the environment of the UE 106. Fordiscussion purposes, reference is made to the previous figures indescribing the process 1000.

At 1002, a UE 106 may determine, based on a poor RF condition(s), toswitch from using an existing audio codec currently being used for anongoing communication session (e.g., a call 102) to using a differentaudio codec. For example, the UE 106 may determine that a value(s)indicative of a RF condition(s) is/are less than a threshold value(s),as described with respect to FIG. 8A, and the UE 106 may determine todowngrade from the existing audio codec (e.g., the EVS-FB codec 118) toa different EVS audio codec that provides lesser audio bandwidth, butgreater audio redundancy and/or link budget.

At 1004, in response to the determination at block 1002, the UE 106 maygenerate audio data 206 based on sound in an environment of the UE 106.The operation(s) performed at block 1004 may be similar to theoperation(s) performed at block 304 of the process 300.

At 1006, the UE 106 (e.g., the audio analyzer 208) may determine basedat least in part on the audio data 206 (e.g., based on an analysis ofthe audio data 206), whether the sound includes frequencies outside of arange of frequencies 210 associated with a human voice. The operation(s)performed at block 1006 may be similar to the operation(s) performed atblock 306 of the process 300, including, for example, determiningwhether music is being played in the environment of the UE 106.Furthermore, as shown by blocks 1008 and 1010, the determination atblock 1006 may utilize machine learning and/or artificial intelligencetechniques. For example, the operation(s) performed at block 1008 may besimilar to the operation(s) performed at block 308 of the process 300,and the operation(s) performed at block 1010 may be similar to theoperation(s) performed at block 310 of the process 300.

If, at 1006, the UE 106 (e.g., the audio analyzer 208) determines thatthe sound does not include frequencies outside of a range of frequencies210 associated with a human voice, such as by determining that music isno longer being played in the environment of the UE 106, the process1000 may follow the NO route from block 1006 to block 1012 where the UE106 may transition to using the different EVS audio codec (e.g., theEVS-SWB codec 114). Switching to using the different EVS audio codec atblock 1012 may include sending a message to the serving base station 108requesting to make the transition, as described herein. By determiningthat music is not being played in the environment of the UE 106 beforeswitching to the less-than-full-band EVS audio codec at 1012, the UE 106can be more confident in the decision to switch to a less-than-full-bandEVS audio codec knowing that the user on the other end of the call 102is unlikely to be interested in hearing non-vocal sounds or frequencies.

If, at 1006, the UE 106 (e.g., the audio analyzer 208) determines thatthe sound includes frequencies outside of a range of frequencies 210associated with a human voice, such as by determining that music isbeing played in the environment of the UE 106, the process 1000 mayfollow the YES route from block 1006 to block 1014 where the UE 106continues the communication session (e.g., the voice call 102) using theEVS-FB codec 118.

It is to be appreciated that additional or alternative factors besidesthe detecting music in the environment of the UE 106 may be taken intoaccount in determining whether to transition to the different EVS audiocodec (e.g., the EVS-SWB codec 114) or not. Such additional oralternative factors may include, without limitation, a location of theUE 106, a type communication session(s) that is ongoing on the UE 106(e.g., media playback, voice call 102, etc.), and/or whether carrieraggregation (e.g., New Radio Carrier Aggregation (NRCA) is beingutilized for the communication session the UE 106 is involved in, amongother possible factors.

FIG. 11 illustrates a flowchart of an example network-side process 1100for adaptively transitioning between audio codecs during an ongoingcommunication session, in accordance with various embodiments. Fordiscussion purposes, reference is made to the previous figures indescribing the process 1100.

At 1102, a network node(s) (e.g., a serving base station 108 and/oranother network node) of a telecommunications network may establish, fora UE(s) 106, a communication session using a first audio codec thatprovides a first audio bandwidth. In some examples, the communicationsession is a voice call 102, such as a VoNR session. In someimplementations, the network node may receive, at block 1102 from a UE106, a session request, such as a SIP message using the SIP INVITEmethod, to request establishment of the call 102 with a terminatingdevice, such as another UE. The session request received at 1102 mayalso include a SDP offer that specifies, among other things, particularcodecs, including audio codecs, that are supported by the UE 106. Theaudio codecs supported by the UE 106 may be listed in order ofpreference, the first codec in the list being a preferred audio codec(or a default audio codec that is used by default if the terminatingdevice also supports that audio codec, and if the RF conditions are goodenough to use that audio codec). Accordingly, the first audio codec maybe listed first in the list of supported audio codecs.

At 1104, the network node(s) may determine whether to switch to using adifferent audio codec during the ongoing communication session (e.g.,the call 102). The determination to switch audio codecs at 1104 may bebased on any of the techniques described herein. For example, thedetermination at 1104 may include receiving audio data 206 generated bythe UE 106 during the communication session (e.g., the call 102) anddetermining, based at least in part on the audio data 206, that sound inthe environment of the UE 106 includes frequencies outside of a range offrequencies 210 associated with a human voice, such as determining thatmusic is being played in the environment of the UE 106. The networknode(s) may use any of the techniques described herein for making such adetermination, such as machine learning and/or artificial intelligencealgorithms. For example, the network node(s) may provide the audio data206 as input to a trained machine learning model(s), and the trainedmachine learning model(s) may generate, as output, a probability that asource of at least some of the sound is not a human voice (e.g., thatmusic is playing in the background of the UE 106). As another example,the determination at 1104 may include determining whether a value(s)indicative of a RF condition(s) associated with the serving base station108 is/are less than a threshold value(s). Additionally, oralternatively, since the network node(s) has access to data that the UE106 may not have access to, the network node(s), at 1104, may determinewhether a value indicative of network congestion and/or a valueindicative of packet delay associated with the serving base station 108is equal to or greater than a threshold value(s). These parameters(e.g., congestion, delay, etc.) may influence the decision to switch toa different audio codec.

If the network node(s) determines to refrain from switching to adifferent audio codec, the process 1100 may follow the NO route fromblock 1104 to block 1106, where the network node(s) continues thecommunication session (e.g., the voice call 102) for the UE(s) 106 usingthe first audio codec. If the network node(s) determines to switch to adifferent audio codec, the process 1100 may follow the YES route fromblock 1104 to block 1108, where the network node(s) may cause the UE(s)106 to switch to using a second audio codec that provides a second audiobandwidth different than the first audio bandwidth. In someimplementations, the network node(s) may send an instruction to the UE106 involved in the communication session to switch audio codecs, andthe UE 106 may initiate the transition by sending a message to theserving base station 108 to transition to the second audio codec, asdescribed herein. In other implementations, the network node(s) mayinitiate the transition by instructing both UEs involved in thecommunication session to switch audio codecs, and the UEs 106 may switchto using the second audio codec.

At 1110, the network node(s) may continue the communication session(e.g., the call 102) using the second audio codec. If upgrading to agreater audio bandwidth, the first audio codec may be at least one ofthe EVS-NB codec, the EVS-WB codec, or the EVS-SWB codec 114, and thesecond audio codec may be the EVS-FB codec 118. If downgrading, thefirst audio codec may be the EVS-FB codec 118 and the second audio codecmay be at least one of the EVS-NB codec, the EVS-WB codec, or theEVS-SWB codec 114.

FIG. 12 is a block diagram of an example communication device 1200configured to perform the techniques and processes described herein, inaccordance with various embodiments. The communication device 1200 mayrepresent a UE, such as the UE 106 described herein, or thecommunication device 1200 may represent a network node that mayimplement at least some of the techniques and processes describedherein. As shown in FIG. 12, the communication device 1200 may includeone or more processors 1202 and one or more forms of computer-readablememory 1204. The communication device 1200 may also include additionalstorage devices. Such additional storage may include removable storage1206 and/or non-removable storage 1208.

In various embodiments, the computer-readable memory 1204 comprisesnon-transitory computer-readable memory 1204 that generally includesboth volatile memory and non-volatile memory (e.g., random access memory(RAM), read-only memory (ROM), erasable programmable read-only memory(EEPROM), Flash Memory, miniature hard drive, memory card, opticalstorage, magnetic cassettes, magnetic tape, magnetic disk storage orother magnetic storage devices, or any other medium). Thecomputer-readable memory 1204 may also be described as computer storagemedia and may include volatile and nonvolatile, removable andnon-removable media implemented in any method or technology for storageof information, such as computer readable instructions, data structures,program modules, or other data. Computer-readable memory 1204, removablestorage 1206 and non-removable storage 1208 are all examples ofnon-transitory computer-readable storage media. Computer-readablestorage media include, but are not limited to, RAM, ROM, EEPROM, flashmemory or other memory technology, compact disc read-only memory(CD-ROM), digital versatile disks (DVD) or other optical storage,magnetic cassettes, magnetic tape, magnetic disk storage or othermagnetic storage devices, or any other medium which can be used to storethe desired information and which can be accessed by the communicationdevice 1200. Any such computer-readable storage media may be part of thecommunication device 1200.

The communication device 1200 may further include input devices 1210(e.g., a touch screen, keypad, keyboard, mouse, pointer, microphone 200,etc.) and output devices 1212 (e.g., a display, printer, speaker, etc.)communicatively coupled to the processor(s) 1202 and thecomputer-readable memory 1204. The communication device 1200 may furtherinclude a communications interface(s) 1214 (e.g., the communicationsinterface(s) 204) that allows the communication device 1200 tocommunicate with other computing devices 1216 such as via a network(s)(e.g., a telecommunications network, cellular network, and/or IMSnetwork). The communications interface(s) 1214 may facilitatetransmitting and receiving wired and/or wireless signals over anysuitable communications/data technology, standard, or protocol, asdescribed herein. For example, the communications interface(s) 1214 cancomprise one or more of a cellular radio, a wireless (e.g., IEEE802.1x-based) interface, a Bluetooth® interface, and so on. In someembodiments, the communications interface(s) 1214 may include RFcircuitry that allows the communication device 1200 to transitionbetween different radio access technologies (RATs), such astransitioning between communication with a 5G NR RAT, a 4G LTE RAT andother legacy RATs (e.g., 3G/2G). The communications interface(s) 1214may further enable the communication device 1200 to communicate overcircuit-switch domains and/or packet-switch domains.

In some embodiments, the computer-readable memory 1204 may include thevocoder 112, which may include the EVS encoder 202, which may includethe audio analyzer 208 and the codec adapter 212, as described above. Inaddition, the memory 1204 may include a RF condition module 1218configured to determine one or more RF conditions (and/or valuesthereof), such as RSSI, RSRP, RSRQ, etc., as described above forimplementing the techniques and processes described herein. One or moreof these components of the communication device 1200 may be configuredto access thresholds 1220, such as a RSSI threshold(s)), RSRPthreshold(s), and/or RSRQ threshold(s), and/or frequency thresholds(e.g., a frequency range(s) 210), as described herein. One or more ofthese components of the communication device 1200 may be further beconfigured to access one or more trained machine learning model(s) 1222,as described herein, such as a model(s) 1222 configured to determinenon-vocal frequencies (e.g., music) in an environment of a UE.

The environment and individual elements described herein may of courseinclude many other logical, programmatic, and physical components, ofwhich those shown in the accompanying figures are merely examples thatare related to the discussion herein.

The various techniques described herein are assumed in the givenexamples to be implemented in the general context of computer-executableinstructions or software, such as program modules, that are stored incomputer-readable storage and executed by the processor(s) of one ormore computers or other devices such as those illustrated in thefigures. Generally, program modules include routines, programs, objects,components, data structures, etc., and define operating logic forperforming particular tasks or implement particular abstract data types.

Other architectures may be used to implement the describedfunctionality, and are intended to be within the scope of thisdisclosure. Furthermore, although specific distributions ofresponsibilities are defined above for purposes of discussion, thevarious functions and responsibilities might be distributed and dividedin different ways, depending on circumstances.

Similarly, software may be stored and distributed in various ways andusing different means, and the particular software storage and executionconfigurations described above may be varied in many different ways.Thus, software implementing the techniques described above may bedistributed on various types of computer-readable media, not limited tothe forms of memory that are specifically described.

We claim:
 1. A computer-implemented method comprising: establishing, bya user equipment (UE), and via a serving base station, a voice callusing an Enhanced Voice Services Full Band (EVS-FB) codec as a defaultcodec, the EVS-FB codec providing a first audio bandwidth; determining,by the UE, and during the voice call, that a value indicative of a radiofrequency (RF) condition associated with the serving base station isless than a threshold value; sending, by the UE, and based at least inpart on the determining that the value indicative of the RF condition isless than the threshold value, a message to the serving base station fortransitioning from using the EVS-FB codec to using a different EnhancedVoice Services (EVS) audio codec that provides a second audio bandwidthless than the first audio bandwidth; and continuing, by the UE, and viaa serving base station, the voice call using the different EVS audiocodec.
 2. The computer-implemented method of claim 1, wherein the valueindicative of the RF condition comprises at least one of: a radio signalstrength indication (RSSI) value; a reference signal received power(RSRP) value; or a reference signal received quality (RSRQ) value. 3.The computer-implemented method of claim 1, wherein the different EVSaudio codec is an EVS Super Wideband (EVS-SWB) codec with Channel AwareMode (CAM).
 4. The computer-implemented method of claim 3, wherein theEVS-SWB codec is used at a bit rate of about 13.2 kilobits per second(kbps).
 5. The computer-implemented method of claim 1, furthercomprising, in response to the determining that the value indicative ofthe RF condition is less than the threshold value: outputting, via theUE, a user prompt associated with transitioning from using the EVS-FBcodec to using the different EVS audio codec; and receiving user inputvia the UE to transition from using the EVS-FB codec to using thedifferent EVS audio codec, wherein the sending of the message occurs inresponse to the receiving of the user input.
 6. The computer-implementedmethod of claim 1, further comprising: determining, by the UE, thatmusic is not being played in an environment of the UE, wherein thesending of the message is further based on the determining that themusic is not being played in the environment of the UE.
 7. A userequipment (UE) comprising: a processor; and memory storingcomputer-executable instructions that, when executed by the processor,cause the UE to: establish, and via a serving base station, acommunication session using an Enhanced Voice Services Full Band(EVS-FB) codec as a default codec, the EVS-FB codec providing a firstaudio bandwidth; determine, during the communication session, that avalue indicative of a radio frequency (RF) condition associated with theserving base station is less than a threshold value; send, based atleast in part on determining that the value indicative of the RFcondition is less than the threshold value, a message to the servingbase station for transitioning from using the EVS-FB codec to using adifferent Enhanced Voice Services (EVS) audio codec that provides asecond audio bandwidth less than the first audio bandwidth; andcontinue, via the serving base station, the communication session usingthe different EVS audio codec.
 8. The UE of claim 7, wherein the valueindicative of the RF condition comprises at least one of: a radio signalstrength indication (RSSI) value; a reference signal received power(RSRP) value; or a reference signal received quality (RSRQ) value. 9.The UE of claim 7, wherein the different EVS audio codec is an EVS SuperWideband (EVS-SWB) codec with Channel Aware Mode (CAM).
 10. The UE ofclaim 7, wherein the computer-executable instructions, when executed bythe processor, further cause the UE to, in response to determining thatthe value indicative of the RF condition is less than the thresholdvalue: output a user prompt associated with transitioning from using theEVS-FB codec to using the different EVS audio codec; and receive userinput to transition from using the EVS-FB codec to using the differentEVS audio codec, wherein sending the message occurs in response toreceiving the user input.
 11. The UE of claim 7, wherein thecomputer-executable instructions, when executed by the processor,further cause the UE to: determine that music is not being played in anenvironment of the UE, wherein sending the message is further based ondetermining that the music is not being played in the environment of theUE.
 12. The UE of claim 7, wherein the communication session is a Voiceover New Radio (VoNR) communication session.
 13. The UE of claim 7,wherein the computer-executable instructions, when executed by theprocessor, further cause the UE to: determine, during the communicationsession, that a second value indicative of the RF condition associatedwith the serving base station is equal to or greater than the thresholdvalue; sending, by the UE, and based at least in part on determiningthat the second value indicative of the RF condition is equal to orgreater than the threshold value, a second message to the serving basestation for transitioning from using the different EVS audio codec tousing the EVS-FB codec; and continuing, by the UE, and via the servingbase station, the communication session using the EVS-FB codec.
 14. Oneor more non-transitory computer-readable media storingcomputer-executable instructions that, when executed by a processor of auser equipment (UE), cause the UE to: establish, and via a serving basestation, a communication session using an Enhanced Voice Services FullBand (EVS-FB) codec as a default codec, the EVS-FB codec providing afirst audio bandwidth; determine, during the communication session, thata value indicative of a radio frequency (RF) condition associated withthe serving base station is less than a threshold value; send, based atleast in part on determining that the value indicative of the RFcondition is less than the threshold value, a message to the servingbase station for transitioning from using the EVS-FB codec to using adifferent Enhanced Voice Services (EVS) audio codec that provides asecond audio bandwidth less than the first audio bandwidth; andcontinue, via the serving base station, the communication session usingthe different EVS audio codec.
 15. The one or more non-transitorycomputer-readable media of claim 14, wherein the value indicative of theRF condition comprises at least one of: a radio signal strengthindication (RSSI) value; a reference signal received power (RSRP) value;or a reference signal received quality (RSRQ) value.
 16. The one or morenon-transitory computer-readable media of claim 14, wherein thedifferent EVS audio codec is an EVS Super Wideband (EVS-SWB) codec withChannel Aware Mode (CAM).
 17. The one or more non-transitorycomputer-readable media of claim 14, wherein the computer-executableinstructions, when executed by the processor, further cause the UE to,in response to determining that the value indicative of the RF conditionis less than the threshold value: output a user prompt associated withtransitioning from using the EVS-FB codec to using the different EVSaudio codec; and receive user input to transition from using the EVS-FBcodec to using the different EVS audio codec, wherein sending themessage occurs in response to receiving the user input.
 18. The one ormore non-transitory computer-readable media of claim 14, wherein thecomputer-executable instructions, when executed by the processor,further cause the UE to: determine that music is not being played in anenvironment of the UE, wherein sending the message is further based ondetermining that the music is not being played in the environment of theUE.
 19. The one or more non-transitory computer-readable media of claim14, wherein the communication session is a Voice over New Radio (VoNR)communication session.
 20. The one or more non-transitorycomputer-readable media of claim 14, wherein the computer-executableinstructions, when executed by the processor, further cause the UE to:determine, during the communication session, that a second valueindicative of the RF condition associated with the serving base stationis equal to or greater than the threshold value; sending, by the UE, andbased at least in part on determining that the second value indicativeof the RF condition is equal to or greater than the threshold value, asecond message to the serving base station for transitioning from usingthe different EVS audio codec to using the EVS-FB codec; and continuing,by the UE, and via the serving base station, the communication sessionusing the EVS-FB codec.